Tobacco and method of treating the same



Juiy 2Q, 1948. F. J. SOWA TOBACCO AND METHOD OF TREATING THE SAIE Filed June 11, 19%

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INVENTOR FRANK J. SOWA B! 2 p a a AITORNEY Patented July 20, 1948 TOBACCO AND Mrrrnon or run SAME TREATING Frank J. Sowa, Crani'ord, N. 1., assignor to American Machine and Foundry Company, a corporation of New Jersey Application June 11, 1942, Serial No. 446,550

12 Claims. (01. 131-17) ably tobacco reduced in an aqueous fluid medium to such a state that all or part ofthe tobacco particles are colloidal or substantially colloidal in size, and if such slurry is sprayed or otherwise applied to shredded cigarette tobacco, smoking tobacco or tobaccos which are to be formed into smoking or chewing articles or shredded for use in making cigarettes, because of the presence of the slurry which is applied preferably to all exterior surfaces of the tobacco pieces, particles or shreads, each shred, particle or piece contains a gel-like film or coating which when dry provides a bulking or stiffening effect to the shreds and pieces so that a longer or firmer feeling cigarette may be made with the same amount of tobacco, while at the same time tobacco treated in this manner satisfies all of the usual tests applied thereto insofar as smokability, quality and value are concerned.

The fact that tobacco treated in this manner has a gel-like coating or film substantially covering the exterior surfaces of each piece greatly contributes to the filling power of tobacco especially in cigarettes so that as a natural result cigarettes produced from treated tobacco have a. firmer feel and in general retain all of the physical characteristics of cigarettes made from a greater quantity of untreated tobacco. One effect, therefore, of treating tobacco in this manner is to increase the relative strength of each shred or piece of tobacco so that there is less likelihood of of shredded cigarette tobacco being broken and converted into shorts during the formation of cigarettes. It will be seen, therefore, that because of the increased strength and toughness imparted to shredded cigarette tobacco, cigarettes formed therefrom will be much less liable to deformation in the case of rather loosely filled cigarettes now in use and especially in cigarettes of long or king size, approximately eighty-five millimeters (85 mm.) in length as compared with -the conventional cigarette length of seventy millimeters (70 mm.), which are particularly subject to deformation and breakage. This is one reason why my treated tobacco has a greater filling power.

My invention, therefore, consists in the novel method of treating tobacco of all types for use in smoking, chewing, etc., by adding thereto quantities of bulking and stiffening whereby longer and firmer feeling cigarettes may be made from the same amount of tobacco. v

My invention also consists in the novel method of applying to all kinds of tobacco to be used for smoking, chewing, cigarette manufacture, cigar manufacture and the like, a coating or slurry consisting of a fluid mixture of finely reduced tobacco particles, which when applied to the sur face of thetobacco pieces, shreds or leaves being treated, acts as a means for strengthening or toughening the tobacco pieces, shreds and leaves so that longer and firmer feeling cigarettes may be made with a given quantity of tobacco. The

fluid mixture can be formed from tobacco leaves, pieces, or tobaccos usually considered as byproducts or waste.

My invention also consists of improved types of smoking and other tobaccos made in accordance with my improved method. In the manufacturing of cigarettes, cigars and other tobacco products, in the course of a period of time large quantities of tobacco such for instance as tobacco dust, scraps, stems and clippings, have been considered as waste and sold as such as low price at a loss to manufacturers. Therefore, cigarette, smoking tobacco, cigar and other tobacco product manufacturers have long wished to make some satisfactory disposition of such products, and especially is this so in the case of waste originating from more expensive tobaccos which have a relatively high initial cost and which at times may be very difiicultjo obtain.

It is an object of my invention, therefore, to

produce a method of resulting in a more efllcient use of tobacco by utilizing dust, stems and scrap, usually considered as waste, by forming it into a slurry consisting of finely divided tobacco particles reduced in a neutralfiuid medium to a size such that all or a large portion of the tobacco particles are substantially colloidal in size and applying this slurry to the main bulk of tobacco being processed for manufacture into cigarettes, cigars, smoking tobacco or other tobacco products in.the usual manner by spraying or otherwise applyin the slurry to the bulk of tobacco so that preferably the entire surface of each piece of tobacco, shred, leaf, particle, etc., is covered with tobacco slurry which upon removal of moisture remains afilxed in gel-like form substan- T48 5 an integral part of the surface of the treated tobacco where it imparts to the pieces. shreds or particles. a stiffening effect.

My invention also consists in a more efllcient e of tobacco through the elimination of waste in the production of tobacco products by utilizing tobacco material formerly considered waste as a constituent part of tobacco products partly made therefrom.

Other objects ofmy invention will be set forth in the following description, it being understood that the above statement of objects is intended generally to explain the same without limiting it in any manner.

In the accompanying drawings which form ,a part of this specification and wherein the several reference characters designate the same or like elements:

Figure 1 is a diagrammatic perspective view showing one method of applying a coating of tobacco slurry or a solution containing colloidal tobacco to the surface of tobacco leaves and the like;

Figure 2 shows diagrammatically, mechanism suitable for use in applying tobacco slurry or a partly colloidal tobacco solution to shredded tobacco; and

Figure 3 is a greatly enlarged cross sectional view of a typical tobacco shred which has been coated with tobacco slurry showing generally the manner in which the slurry adheres to the tobacco surface.

The slurry, which can also be designated partly colloidal tobacco .or colioidally bound tobacco, may be formed in any desired manner, similar to that set forth in co-pending applications, Serial No. 414,221, filed October 9, 1941, by F. H. Wells and F. J. Sowa for Tobacco sheet material, which has issued as Patent No. 2,433,877, dated January 6, 1948, and Serial No. 446,366, filed June 9, 1942, by F. J. Sowa and F. F. Tone for Method for producing tobacco web material. That is, when tobacco waste in the form of powder is to be converted into a slurry or partly colloidal tobacco for use in processing tobacco for formation into cigarettes, cigars or other smokable tobacco products, the tobacco powder can be placed in a ball mill or colloidal mill and ground for a suitable time to reduce all or a part thereof to a colloidal state. The same procedure can be followed if tobacco is in the form of small or large fragments,

contents of the stem boxes of cigarette machines containing one or more types of tobaccos, clippings, tobacco chips, other mixed tobacco byproducts, and the like. For best results the tobacco should be clean, and dust containing over thirty per cent undesirable inert material, such as sand, should not. be used since such materials act as mechanical diluents and reduce the practical value of the coating mixture.

When tobacco is dry ground, a selected quantity is preferably dried to remove most of the moisture retained therein, after which it is broken up into small pieces in anysuitable manner. It has been found that dry grinding proceeds faster and more satisfactorily when the moisture content is reduced below five per cent. Any suitable device may be employed for reducing the broken up dried tobacco to final size. For instance, the tobacco may be placed in a ball mill and ground to colloidal, or substantially colloidal size or to a fineness such that it is easily dispersible in a neutral fluid medium, such as water. This method of grinding, however, is relatively slow and the amount of time consumed varies according to the quantity of tobacco selected for grinding, the size of the mill and the balls or pebbles used therein, and the speed of operation of the mill. For optimum results the charge should not exceed the volume of voids in the mill. The amount of time required is also a function of the size and condition of the tobacco before it is placed in the mill. For instance, if the material being comn'iinuted is small particle size at the outset, less time will be required than if the material is in the form of broken up leaves and stems.

If more rapid material grinding is preferred, a plate or disk type colloidal mill may be used, in

which case a selected quantity of tobacco or other leafy material can be reduced advantageously to extremely fine size in the matter of minutes.

The mixture is ground for a period sufficient to reduce the solid material to extremely fine size, wherein all or preferably the greater part of the particles are in a colloidal state. It has been found that the grinding time varies over a considerable range, and that when this mixture is ground for a period ranging between six and eight hours in a 1 /4 gallon mill, using /2' inch flint balls at 45-50 revolutions per minute, advantageous results are obtained. If the tobacco to be groundis in the form of parts of leaves, or the like, a selected quantity is preferably broken up in order to expedite its reduction to a partly coiioidal tobacco, placed in a grinding device, such as a ball mill, and an aqueous medium, such as water, is added thereto to establish a suitable ratio, say of 1:8 depending upon the type of tobacco.

' The tobacco being formed into colloidally bound tobacco may also be subjected to dry and wet grinding. If this type of grinding is resorted to, selected tobacco is preferably dried and then ground either in a disk type colloidal mill rapidly in a few minutes or more slowly, about three hours, in a ball mill, as described hereinabove. When the material has been reduced to proper size, as described above, it is introduced into a second grinding device, such as a ball mill or left in the first mill and mixed with a suitable quantity of fiuid in order to prepare it for a wet or final grinding. Any fluid, preferably neutral in nature such as water or dilute ethyl alcohol, with which a colloidal dispersion will take place, can be used. It is important that a fluid be chosen which will have little or no deleterious effects upon the tobacco or otherwise change its normal physical characteristics insofar as taste, odor and color are concerned, since they are carried over into the final product and retained therein. Water forms a very satisfactory medium and is usually used in an amount suitable to form a fluid mixture. A ratio of 1:8 by weight may be used, although other suitable proportions, as described hereinabove. will give the same or satisfactory results.

As in the case of dry grinding, the period or grind is dependent to the same extent upon the quantity of material being ground, as represented by the mixture of fluid and pulverized tobacco, the capacity of the ball mill, if a ball mill is selected as the grinding mechanism, the size of balls .and speed of operation of the mill. I havefound that a ball mill is a satisfactory device ,t6.use in'carrying out this step of my process and that with a 1 /4 gallon mill containing 800 cubic centimeters of water and grams of tobacco constituting the wet grind mixture or slur ry, the time required to reduce the charge of powdered tobacco to fine particles or partly colloidal state ranges between one and ten hours, and that on an average of six hours has proven to be an advantageous period.-

The result of grinding tobacco in any of the forms mentioned in a fluid medium is a slurry, or solution containing colloidal tobacco or a tobacco sol. This product is a thick viscous liquid about the viscosity of heavy cream, although viscosity will vary depending upon the type of tobacco used and the ratio of tobacco to fluid. If necessary for properapplication to tobacco to be treated, the slurry can be diluted.

The colloidally bound'tobacco solution or slurry preferably should be applied to the tobacco being processed as Soon as possible after being completed because it has been found that it tends readily to ferment if allowed to standfor several hours, say three or four, unless refrigerated. A small quantity of preservative such as benzoate of soda can be used to prevent fermentation without unsatisfactory results to the final product. In general, however, this procedure is unnecessary.

If a slurry is produced by mixing together a selected quantity of ground tobacco and water in a ratio of say 1:6 or 1:8, or other proportion, such as described above, an intimate suspension can be obtained byvmixing the material mechanically in any known manner as desired, the particles may be dispersed throughout the liquid phase by agitating with steam thereby effecting a proper dispersion.

The colloidally bound tobacco solution or slurry can be applied to tobacco to be treated as soon as grinding is' completed or it can be treated by heat at atmospheric pressure or greater heat under elevated pressure, in the manner similar to that described in the above mentioned co-pending Sowa and Tone application, as by treating tobacco or slurry in an autoclave for a period of time suflicient to hydrate and swell the particles until substantially a hydrosol is formed, especially insofar as the finest or'colloidal particles are concerned. Also, during the time of hydration there is some hydrolysis takin place and it is from this action that it is believed that the heat accelerates the hydration of the tobacco particles and also accelerates the limited amount of hydrolysis of such materials contained in tobacco as glucosides, thereby increasing the aroma of .the resulting tobacco product and greatly enhancing its desirability for use in forming smoking tobacco articles.

Heat at atmospheric pressures or higher heat I at elevated pressure treatment may be given either before the tobacco is converted into a slurry or after. If it is resorted to after the formation of the slurry, it is preferred to place a quantity of the slurry in a pressure cooker and cook it therein at a pressure of fifteen pounds per square inch for a period of three hours at 250 F. water vapor temperature. Other pressures and cooking periods can be used advantageously. For instance, if the pressure is increased then the desired result is effected in a shorter time. Also, if desired the mixture can be cooked at normal atmospheric temperature by heating in a reaction flask connected to a reflux condensor for about flve hours and satisfactory results are obtained. During the heat treatment of the slurries, it is advantageous to a itate the slurry or suspension as by shakin or stirring, or in any other suitable manner such as bubbling live steam into the suspension because this breaks up loidally bound or partly colloidal tobacco can be handled in several ways, as by dipping, spraying,

or in some other known manner of coating. Re-

ferring to the drawings, which show the preferred method. in Figure 1 tobacco L of full leaf or partial leaf size can be placed upon a conveyor I which is traveling in the direction of the arrow A beneath one or more spray nozzles 2 ad- Justably mounted upon a conduit 3 connected through a valve 4 to a source or supply, designated generally 5, provided with a filling opening closed by a removable cap 6 and a pipe 1 leading from an air compressor of any conventional type (not shown) which forces the colloidally bound tobacco in its fluid medium through the conduit 3. As shown in Figure 1, one surface of the leaves being treated will be coated with the tobacco slurry as it passes beneath the nozzles 2 for discharge from the conveyor. The travel of conveyor i is so regulated by any suitable conventional driving mechanism (not shown) as to permit an even application of slurry over the entire exposed surface of the tobacco being treated.

In some instances it may be desired to coat only one face of the tobacco, but if it should be desirable to coat both faces, the tobacco may be discharged from conveyor i upon a curved guide 8 suitably mounted adjacent the end of conveyor I so that as the partially coated leaves are discharged from the conveyor i they will be guided by means of guide 8 onto the upper surface of the conveyor 9, which in the embodiment shown is located directly beneath the conveyor I. although any other arrangement of the conveyors may be utilized. The partially coated leaves or pieces L are inverted by movement along guide 8 and arrive on the upper surface of conveyor 9 where they assume the general positions shown in Figure 1, and as the conveyor 9 travels in the direction of arrow B, the leaves are passed beneath one or more nozzles l0 similar in construction to nozzles 2 and the surface of the leaves are thus coated with colloidally bound tobacco or tobacco slurry in the same manner as on conveyor l. Nozzles ID are adjustably mounted on conduit H provided with a valve i2 connected to the source of supply 5. Nozzles 2 and i0 and valves 4 and I2 may be of any conventional design and the valves are so arranged with respect to the source of supply 5 that either valve 4 or valve, I2 may be closed to cut off the supply of tobacco slurry through conduit 3 or conduit ll depending upon whether the colloidally bound tobacco is to be applied to one or both faces of the tobacco. Scrapers 28 mounted on collecting receptacles 28 can be used to remove slurry from conveyors l and 9, although only one is shown, so that as the conveyors travel, any material adhering to the conveyors will be scraped therefrom, and fall into receptacles 28 for reuse.

Tobacco treated in the manner just described can be stored and bulked for a time in order to allow proper drying of the slurry applied thereto, after which it is handled in the usual manner determined by whether the tobacco is to be formed into cigarettes, cigars, or smoking tobacco, or it can be dried by mechanical means (not shown), stored or processed.

In Figure 2, mechanism is shown for treating shredded tobacco and applying thereto colloidally boundtobacco or slurry prior to the formaaccuse 7 tion of the tobacco into cigarettes, and either before or after the cigarette tobacco has been "cased. The slurry is placed in a source of supply It provided with a filling opening having a removable cap I! and a compressed air pipe I6 fixed to any suitable source which is effective for forcing the slurry through a conduit l1 and an adiustably mounted nozzle l8 connected thereto into the interior of a slowly revolving drum It. This drum may be of any well-known construction and is of the type commonly employed in the art for "casing tobacco preparatory to its being made in to cigarettes. Tobacco is fed into the drum in the direction of the arrow C from the far end of the drum (not shown) and by means of baffles 20 is tumbled about in the drum and advanced over an outer flaring portion 2! into a suitable storage box or receptacle 2!. During the movement of the tobacco D through the drum i9, colloidally bound tobacco is sprayed upon the tumbling tobacco so that substantially each and every shred of tobacco receives an intimate coating of the colloidally bound tobacco before it is finally discharged into storage box 22. Nozzle I8 is so mounted that it can be positioned at the best possible angle with respect to the interior of the drum for application of the slurry to tobacco and (as shown in Figure 2) is located substantially on the longitudinal axis of the drum although this position can be changed, if desired. Valve 24 in conduit i1 controls the quantity of colloidally bound tobacco issuing from the nozzle i1 and cuts off the entire supply at the end of a run or whenever necessary. As shown diagrammatically in Figure 2, slurry coated tobacco is placed in storage S for a period of time after coating, usually twenty-four or forty-eight hours, after which it is introduced into a cigarette manufacturing machine M and formed into cigarettes.

Colloidally bound tobacco can also be applied to shredded tobacco in drum l9 as a part of the casing, which in American practice is usually applied to cigarette tobacco sometime during its processing from leaf form into shredded prepared tobacco. Obviously smoking tobacco or other finely divided tobacco can be treated with colloidally bound tobacco in a similar manner in drum l9.

Referring to Figure 3, which shows a greatly exaggerated cross sectional view of a piece of tobacco coated with a slurry containing colloidal tobacco, it will be seen that in general the piece of tobacco is covered with a thin film F or gellike coating which in general covers the entire exterior surface of each shred, piece, or leaf oi tobacco being coated, although in some instances the coating may not be as uniform and even as indicated in Figure 3. This figure, however, is merely-diagrammatic and indicates one possible appearance of tobacco treated with a' sol containing colloidal tobacco.

Any desired quantity of colloidally bound tobacco or slurry can be applied to a, given batch of tobacco, due to the fact that the percentage of tobacco will vary in accordance'with the type of tobacco being treated for the ultimate use thereof, although the percentage of tobacco by weight made into slurry will probably not exceed 25 per cent. In most instances the desirable range will probably be between of 1 per cent and 10 per cent. For instance, when 7 pounds of slurry, using A pound of Virginia Bright tobacco was applied to 75 pounds of cased cigarette tobacco, after which the treated tobacco was several coatings or applications until the entire dried to reduce the moisture content to that normall found in cigarette tobacco, say between 10 and 12 per cent and then allowed to stand or bulk for forty-eight hours, good results were obtained and cigarettes made therefrom were of very good quality. Good results were also obtained with seventy-five pounds of cased shredded cigarette tobacco treated with eight pounds, two ounces of tobacco. slurry containing three-quarters of a pound of tobacco, after which the treated tobacco was dried to normal moisture content, as mentioned above, bulked for forty-eight hours, and made into cigarettes. In both instances the finished cigarettes had an excellent feel and a minimum of shorts.

Particles of tobacco treated with 2, 4, 6, 8 and 10 per cent slurry, that is 2 per cent, etc., by weight of tobacco made into slurry, resulted in greatly strengthened tobacco shreds, which in being made into cigarettes resulted in fewer shorts and cigarettes of generally improved character and quality.

As stated hereinbefore, various ratios of tobacco to fluid medium can be used as 1:6, 1:8, and more or less, depending upon the type of tobacco being made into slurrles and the desired viscosity of the slurry for application to tobacco undergoing treatment. If for any reason a slurry is too viscous for application, as by spraying to the surface of tobacco being treated, it may be diluted in order to insure better application theretof to the portions of tobacco being processed. A given quantity of tobacco can be applied to a batch of tobacco, all at one time, after which the excess moisture is removed or the tobacco is dried until the normal moisture content is reached, which as stated above may range from 10 to 12 per cent although it may be less or slightly more. If a large quantity of slurry is to be applied to a given batch of tobacco, the latter may be treatedto quantity of slurry has been applied thereto. If this procedure is followed after each application of slurry, the tobacco is dried to lower themoisturecontent, preferably to normal, an additional amount of slurry is then applied, the tobacco being treated is again dried as before, and so on until all of the slurry has been applied thereto, after which the completely coated tobacco is dried to normal moisture content and further prepared for manufacture, as described hereinabove.

Tobacco treated in this manner, to all intents and purposes, has the identical appearance of ordinary shredded tobacco and can be run through cigarette machines in a normal manner without any additional precautions.

While the preferred embodiments of the invention have been described, it is to be understood that the invention is not confined to the specific method steps for carrying out the method herein set forth, by way of illustration, as it is apparent that many changes and variations may be made therein, by those skilled in the art, without departing from the spirit of the invention or exceeding the scope of the appended claims.

What is claimed is: v

l. The method of processing tobacco which comprises reducing a selected quantity of tobacco to a substantially colloidal state in a fluid medium to form a sol, subjecting said sol to heat for a period of time sufiicient to accelerate the hydration of substantially all of said tobacco dspersed in said fluid medium, and then applying said heat treated sol to the surface of tobacco to be treated.

2. The method of processing tobacco which comprises reducing a selected quantity of tobacco to a substantially colloidal state in water to form a hydrosol, subjecting said hydrosol to heat for a period of time sufiicient to accelerate the hydration of substantially all of said tobacco dispersed in said water, and then applying said heat treated hydrosol to the surface of tobacco to be treated.

3. The method of processing tobacco which comprising reducing a selected quantity of tobacco in a liquid medium to form a mixture containing colloidal tobacco, hydrating said colloidal tobacco in said medium, spraying said, mixture upon the surface of a selected quantity of shredded tobacco, and removing excess moisture from said tobacco whereby said colloidal tobacco forms a gel-like. film substantially covering the surface of said shreds of tobacco.

4. The method of processing tobacco which comprises reducing a quantity of tobacco in a' fluid medium so as to contain suspended particles of substantially colloidal size and form a mixture containing colloidally bound tobacco,

subjecting said 'mixture to heat and pressure for a period of time to thereby form substantially a hydrosol, and spraying said hydrosol upon the surface of a selected quantity of tobacco.

5. The method of processing tobacco which comprises reducing a quantity of tobaccodn a fiuid medium so as to contain suspended particles of substantially colloidal size and form a.-

mixture containing colloidally bound tobacco, subjecting said'mixture to heat and pressure for a period of time to thereby form substantially a hydrosol, spraying said hydrosol upon the surface of a selected quantity of tobacco, and removing moisture from said treated tobacco. whereby a gel-like film of colloidal tobacco re-' filling power of tobacco which comprises reducing a selected quantity of tobacco in a liquid medium to form a mixture containing colloidal tobacco, spraying said mixture upon the surface of a selected quantity of shredded tobacco, and reducing the moisture content in said treated tobacco to between and 12 per cent whereby said colloidal tobacco forms a gel-like. stiffening film substantially covering the surface of said shreds of tobacco.

' 10. The method of increasing the filling power of shredded tobacco which comprises selecting a quantity of shredded cigarette tobacco to be treated, selecting a given quantity of a sol containing hydrated colloidal whole tobacco for application to said tobacco, successively applying said sol to said tobacco, and drying said treated tobacco between applications of said sol until the selected quantity of sol has been applied to said tobacco to be treated, and generally reducing the moisture content in said treated tobacco to a point not in excess of 12 percent.

11. Shredded cigarette tobacco comprising natural tobacco shreds wherein substantially all shreds are provided with a strengthening coating consisting of a solid stiffening film formed from a gel containing hydrated colloidal whole tobacco and water. z

12. The method of processing tobacco to increase its filling and bulking qualities which comprises reducing a selected quantity of tobacco in a liquid medium to form a whole tobacco mixtobacco, and reducing excess moisture in said colloidal tobacco dispersed in water, and containing substantially all original soluble and insolu-- ble constituents, and then drying said tobacco to make the strands of said tobacco stiffer.

7. Shredded cigarette tobacco comprising tobacco wherein substantially all the individual shreds are treated with a stiffening agent consisting of a tobacco sol containing substantially all original soluble and insoluble tobacco constituents applied to said tobacco to increase the stiffness of the shreds thereof.

8. The method of increasing the filling power of filler tobacco for use in smoking which consists in applying to said'tobacco a sol containing colloidal whole tobacco between V; of 1 per cent and 10 per cent by weight for 100 pounds of tobacco treated, and drying said treated tobacco to form upon the surfaces thereof a pellicle of natural colloidally bound tobacco, said tobacco forming said pellicle containing substantially all soluble and insoluble constituents origina ly present therein.

9. The method of increasing the bulking and treated tobacco to between ten and twelve and one-half per cent by weight.

- FRANK J. sows.

, assurances orrnn The following references are of record in the file of this patent: V

UNITED STATES PATENTQ.

Number I Name Date 46,233 Hale Feb. 7, 1865 48,689 Huse July 11, 1865 1 64,591 Stayman May 7, 1887 169,182 Broseker Apr. 3, 1877 203,766 Picket May 14, 1878 0 217,787' 'Bolles July 22, 1879 1 267,764 Wood Neg. 21, 1882 858,289 Hondius June 25, 1907 1,018,844 Moonelis Feb. 6, 1912 1,716,250 'I'hiele June 4, 1929.

1,972,718 Sharllt Sept. 4. 1.934

, FOREIGN PATENTS Number Country Date 298,151 Great Britain Jan. 31, 1929 215,370 Germany Oct. 25, 1909 

